Holden Neurodiagnostics Lab

A.  What is an Ambulatory EEG (aEEG)?

Ambulatory electroencephalography (aEEG) monitoring is an EEG that is recorded at home.  It has the ability to record for up to 72 hours.  The aEEG increases the chance of recording an event or abnormal changes in the brain wave patterns.

B.  Why am I getting an an aEEG?

The aEEG is used to record abnormal brain activity that could not be recorded with the regular 20 minute EEG recording.  If abnormal activity only happens a few times a day or during certain times of the day, the aEEG will be able to capture and record those events that would have been missed with the regular EEG. It can help a physician to diagnoses episodes or certain symptoms that are suspected to be due to seizures or capture electrographic seizures without symptoms (silent seizures).

This test can also be used if you continue to have seizures after trying different medications and to confirm or rule out the diagnosis of epilepsy.

C.  How do I prepare for the test? 

• Wash your hair the night before or the day of the test, but don't use any conditioners, hair creams, sprays or styling gels. Hair products can make it harder for the sticky patches that hold the electrodes to adhere to your scalp. If you have weaves or braids, they may need to be removed before a test can be completed.

• Wear a front opening shirt
• Take your usual medications unless instructed otherwise.
• Bring a list of medications with you to your appointment

D.  How is the test performed?

You'll feel little or no discomfort during an aEEG. The electrodes will not transmit any sensations. They just record your brain waves.

Here are some things you can expect to happen during an aEEG:

• A technician measures your head and marks your scalp with a special pencil, to indicate where to attach the electrodes. Those spots on your scalp may be scrubbed with a gritty cream to improve the quality of the recording.
• A technician attaches flat metal discs (electrodes) to your scalp using a special adhesive. Sometimes, an elastic cap fitted with electrodes is used instead. The electrodes are connected with wires to an instrument that amplifies — makes bigger — the brain waves and records them on computer equipment.

Once the electrodes are in place, your head will be wrapped with gauze to help keep the elctrodes in place during your normal everyday activities.

The recorder device is attached to a strap that will go around your neck and the wires can be worn inside or outside of your clothing.

• Go about your normal daily routine except for showering.  It is very important the equipment does not get wet, please keep all equipment away from water completely.  Other than that, go about your normal day.
• During the test keep a written log of your events. The technologist will give  you a log to keep track of any events or symptoms that are suspected to be result from seizures, "funny feelings" or anything you feel would be helpful for the doctor to know during the recording. 
• During the 48-72 hours of recording you will need to change batteries in the recording device.  A 24 hour study does not require battery change.  The technologist will give you instructions on how the batteries are accessed and replaced in the equipment.
• Please return to the lab at your assigned time.  The technologist will give you a specific time to bring back the equipment and be disconnected. Be sure to bring your log with you when you return the equipment.  Failure to return the equipment on time and/or without the log will delay your results and will impact another patient scheduled to have the study using your equipment.

E.  How do I get my results?

After the test, the technician removes the electrodes, your study will be downloaded to our secure server for the physician specially trained in EEG/Epilepsy to read.  Results are generally available within a week after the test completion.  The results will be sent to the physician that ordered the study.

A. What is an EEG?

An electroencephalogram (EEG) is a test that records electrical activity in your brain using small, flat metal discs (electrodes) attached to your scalp. Your brain cells communicate via electrical impulses and are active all the time, even when you're asleep. This activity shows up as wavy lines on an EEG recording.

An EEG is one of the main diagnostic tests for epilepsy. An EEG may also play a role in diagnosing other brain disorders.

B. Why am I getting an EEG?

An EEG can determine changes in brain activity that may be useful in diagnosing brain disorders, especially epilepsy. An EEG can't measure intelligence or detect mental illness. An EEG may be helpful for diagnosing or treating the following disorders:

• Epilepsy or other seizure disorder
• Unexplained loss of consciousness or syncope
• Brain tumor
• Head injury
• Brain dysfunction that may have a variety of causes (encephalopathy)
• Inflammation of the brain (encephalitis)
• Stroke
• Sleep disorders
• Dementia

An EEG may also be used to confirm brain death in someone in a persistent coma. A continuous EEG is used to diagnose status epilepticus (recurrent or continuous seizures), help find the right level of anesthesia for someone in a medically induced coma.

C. How do I prepare for the test? 

• Wash your hair the night before or the day of the test, but don't use any conditioners, hair creams, sprays or styling gels. Hair products can make it harder for the sticky patches that hold the electrodes to adhere to your scalp. If you have weaves or braids, they may need to be removed before a test can be completed.
• Avoid anything with caffeine on the day of the test, because caffeine can affect the test results.
• Take your usual medications unless instructed otherwise.

If you're supposed to sleep during your EEG test, your doctor may ask you to sleep less or even avoid sleep entirely the night before your EEG.

D. How is the test performed?

You'll feel little or no discomfort during an EEG. The electrodes don't transmit any sensations. They only record your brain waves.

Here are some things you can expect to happen during an EEG:

• A technician measures your head and marks your scalp with a special pencil, to indicate where to attach the electrodes. Those spots on your scalp may be scrubbed with a gritty cream to improve the quality of the recording.
• A technician attaches small, flat metal discs (electrodes) to your scalp using a special adhesive. Sometimes, an elastic cap fitted with electrodes is used instead. The electrodes are connected with wires to an instrument that amplifies — makes bigger — the brain waves and records them on computer equipment.

Once the electrodes are in place, an EEG typically takes 30 60 minutes. If you need to sleep for the test, it may take up to three hours.

• You relax in a comfortable position with your eyes closed during the test. At various times, the technician may ask you to open and close your eyes, perform a few simple calculations, read a paragraph, look at a picture, breathe deeply (hyperventilate) for a few minutes, or look at a flashing light.
• Video is frequently recorded during the EEG. Your body motions are captured by a video camera while the EEG simultaneously records your brain waves. This combined recording may help your doctor diagnose and treat your condition.

E. How do I get my results?

After the test, the technician removes the electrodes, your study will be downloaded to our secure server for the physician specially trained in EEG/Epilepsy to read. Results are generally available 24-48 hours after the test completion. The results will be sent to the physician that ordered the study.

A. What is EMG/NCS?

This is a specialized electrical test of your muscles and nerves. It consists of two parts. First NCV (Nerve Copnduction Study) is performed by a technologist using a small electrical impulse to stimulate the nerve and record the response from nerve/ muscle. Thena second part is called EMG or ectromyography, which consists of a needle exam (very small, thin needle inserted into your muscles to record electrical activity) performed by the physician. The EMG part is performed in conjunction with NCV and is not always needed. Your physician’s request for the type of the test and your exam determines the need and extent of the testing.

B. Why am I getting an EMG/NCS?

The purpose of the test is to identify and localize where your symptoms are coming from. These symptoms can be: Pain, Weakness, Numbness and Tingling. Some common disorders that are confirmed by EMG/NCS:

• Carpal Tunnel Syndrome
• Peripheral neuropathy
• Diabetic Neuropathy
• Myopathy
• Radiculopathy (pinched nerve)
• Sciatica or Lumbar radiculopathy
• Trauma

C. How do I prepare for the EMG/NCS? 

• Take a shower the day of test (night before is okay); do not use any vaseline, lotion. oils, skin conditioners, medicated soap or moisterizing soap
• Wear loose fitting clothes; bring shorts to wear with lower extremity tests (feet and legs)
• Follow your physicians instructions regarding your medication.
• Arrive at your scheduled time, being late more than 15 minutes could result in your appointment being rescheduled.

D. What to expect during your EMG/NCS?

• An EMG Physician will take a brief history about any injuries and symptoms you are experiencing and complete a short physical exam.
• You may be asked to change into a hospital gown.
• A heating pack may be applied to the area being tested to maintain skin temperature
• A technologist will comnplete the NCS portion of the test. They will clean the area's being tested with some alcohol, take some quick measurements and mark the area's being tested.
• Sticky electrodes will be placed over the area being tested. The electrodes will be connected to the equipment with three wires. The technologist will then deliver and an electrical stimulus (small electrical impulse) to the nerve . The stimulus may be applied to several points along the nerve.
• After the technologist completes the NCS portion, the results are reviewed by the EMG Physician. After the review, the technologist may need to return and complete additional studies.
• If no other studies are required the physician will enter the room and complete the EMG portion of the test. They will take a very small needle and insert it into some of the muscles in the area's being tested. There will be a sound of muscle fibers working when the needle is inserted. The physician may ask you to perform some simple tasks during the study.
• Once the test has been completed, you will get dressed an go home.
• There are generally no complications associated with this study, only some redness or tenderness in the areas where the study was performed. A cold compress can be used to relieve the slight discomfort, if necessary.

E. How do I get my results?

Results from your test are generally completed within 24-48 hours. The results will be communicated back to your physician that ordered the study.

A.  What is an Epilepsy Monitoring Unit (EMU?)

This is a specialized unit in the hospital where a patient is admitted for 3-5 days for continuous monitoring of brain activity using EEG and Video.  This gives your doctor a better understanding of your seizures by seeing how your brain functioning and what you are physicially doing during the event.

B.  Why am I being admitted to the EMU?

The EMU is used to record abnormal brain activity during seizures that could not be recorded with the regular 20 minute EEG or Ambulatory EEG (aEEG). As the study is performed in controlled setting of the hospital, the physician can lower or stop your seizure medications to increase chance of rfecording seizures during the study. This allows the epileptologist to have a very comprehensive understanding of your seizures.

This test can also be used if you continue to have seizures after trying different medications and to confirm or rule out the diagnosis of epilepsy and also to help locate the part of the brain where seizures start.

The monitoring has 2 components:

1. Digital Video Recording: A camera will record all of your physical activity while your are having your EEG recorded.  There will be an EEG Technologist in the monitoring room at all times to watch you and record any events during your stay.  The technologist will also interact with you during and after an event to test your speech, memory and response to specific questions.  These simple things will help us to identify the type of event and where in the brain it has occurred.
2. EEG Recording:  While in the EMU you will have continuous EEG (brain waves) recorded.  This will allow us to see any abnormal brain patterns that happen, even if you are unaware they are happening.

In some cases we will do a test called Ictal SPECT scan.  This will be performed just like a regular EMU admission, but a specialized tech will be at your bedside and wait for an event to occur.  When an event is identified, the technologist will inject a small amount of the tracer compound into your vein through an IV (intravenous).  The tracer is attracted to the part of the brain that is causing theseizure.  You will then be transported to another department with a specialized scanner for an imaging study.  This will give us very important information as to where the seizure originated in the brain.   

C.  How do I prepare for the EMU Admission? 

To prepare for an EMU Admission:

• Wash your hair the night before or the day of the test, but don't use any conditioners, hair creams, sprays or styling gels. Hair products can make it harder for the sticky patches that hold the electrodes to adhere to your scalp. If you have weaves or braids, they may need to be removed before a test can be completed.

• Wear loose fitting clothes
• Follow your physician’s instructions regarding your medication.
• Arrive at your scheduled time, delays can occur if you are late
• You may bring electronics (laptop etc...) to use during your stay.
• Internet and cable are provided.
• Please be sure your transportation is set up to and from the hospital
• Visitors are allowed during your EMU admission and a family member or loved one who is familiar with the seizure is encouraged to stay with the patient.

D.  What to Expect During your EMU Visit?

Here is what you can expect during an EMU Admission:

• In order to help you have a seizure or event your medications are typically reduced prior to or the same day of your admission (Follow Doctors Instructions). 
• A technician measures your head and marks your scalp with a special pencil, to indicate where to attach the electrodes. Those spots on your scalp may be scrubbed with a gritty cream to improve the quality of the recording.
• A technician attaches flat metal discs (electrodes) to your scalp using a special adhesive. Sometimes, an elastic cap fitted with electrodes is used instead. The electrodes are connected with wires to an instrument that amplifies — makes bigger — the brain waves and records them on computer equipment.

Once the electrodes are in place, your head will be wrapped with gauze to help keep the electrodes in place during your EMU Admission.

The recorder device is attached to a strap that will go around your neck and the wires can be worn inside or outside of your clothing.  The video will record 24 hours a day.  The video will not follow you into the bathroom. 

• If you move to sit in a different part of the room, the camera will be adjusted.  Please let a nurse or the technologist know when you need to use the rest room.  A family member or nurse can assist you to the bathroom. 
• Our EEG Technologists check the electrodes daily to reapply or fix them as necessary.  You will not be able to wash your hair or shower during your EMU admission.
• At your bedside you have a nurse alarm and an event button connected to the EEG Equipment.  If you feel like you are going to have a seizure, "Push the Event Button".  If your event happens suddenly, a family member can press the button for you.  The technologist will go over these steps with you when you arrive.
• During an event, a technologist will come to your room immediately to keep you safe, observe the event and alert the nursing staff.  The nursing staff will come into the room and perform their assessments (blood pressure, oxygen level, etc..)
• Sleep deprivation (staying awake for 24 hours), hyperventilation (breathing exercise), photic stimulation (strobe lights) may be used to help induce an event.  Whenever your brain is tired, it is more likely to have an event.
• During your hospital stay an EMU physician who is specially trained in EEG/Epilepsy will be responsible for your care and will be reviewing your video-EEG recording daily and will see you daily along with the EEG/Epilepsy fellows and neurology residents.Typically, the physician would like to record several of your seizures to properly diagnose type and location of seizures. The EMU physician will let you know how many seizures are needed.

E.  How do I get my results?

After your EMU admission, the technician removes the electrodes, your study will be downloaded to our secure server for the physician specializing in EEG/Epilepsy to read.  Results are generally available a week after your admission.  The results will be sent to the physician that ordered the study.

• AEP (Auditory Evoked Potential)
• VEP (Visual Evoked Potential)
• USSEP (Upper Somatosensory Evoked Potential)
• LSSEP (Lower Somatosensory Evoked Potential)

A.  What is an Evoked Potential?

This is a specialized electrical test that measures the electrical activity of your brain in response to the stimulation of your sensory nerves.   

B.  Why am I getting an Evoked Potential?

The purpose of the test is to identify and localize where your symptoms are coming from.  These symptoms can be:

• Weakness, Numbness and Tingling, (USSEP,LSSEP)
• Hearing Issues or Ringing in the ears, Dizziness or vertigo (AEP)
• Visual Disturbances like blurry or double vision. (VEP)

C.  How do I prepare for the Evoked Potential? 

• Take a shower the day of test (night before is okay); do not use any vaseline, lotion. oils, skin conditioners, medicated soap or moisterizing soap
• Wear loose fitting clothes; bring shorts to wear with lower extremity tests (feet and legs) (for LSSEP, USSEP only)
• Follow your physicians instructions regarding your medication.
• Arrive at your scheduled time, being late more than 15 minutes could result in your appointment being rescheduled.

D.  What to expect during your Evoked Potential?

An evoked potential test can be done as an outpatient or during a hospital stay.  Generally the test follows this process:

• You will be asked to remove any jewelry, clothing, wigs, hair extensions or weaves that may interfere with the test
• If you are asked to remove any clothing you will be given a gown or you will be instructed to bring shorts with you to wear during the test.
• You will be asked to relax in a reclining chair or lie on an exam table
• A technologist will attach the electrodes with paste.  The electrode locations will vary based on on the test being performed.

Visual Evoked Potential Procedure:

• You will be seated a few feet away from a video monitor
• A patch will be placed over one eye while the other eye is tested
• The technologist will do a brief vision test (looking at a card or wall mounted sign)
• You will be asked to focus on a dot in the center of the TV monitor
• The TV monitor will be a checker board pattern changing from black to white, it is important that you stay relaxed and stare at the dot for the entire study.  The technologist will give you a break between stimulating left and right eye
• Test takes about 45 minutes to one hour to complete

Auditory Evoked Potential Procedure:

• You will sit in a quiet room wearing headphones.
• A technologist will check your hearing
• A technologist will place few electrodes on your head and ears
• A clicking sound (auditory stimulus) will be delivered through the earphones to the ear being tested and a masking noise (wooshing sound) in the opposite ear.
• Test takes about 45 minutes to one hour to complete

Upper and Lower Somatosensory Evoked Potentials: 

• A technologist may place electrodes on the scalp, neck, shoulders, back, arms and legs depending on the study ordered.
• A small continuous electrical impulse is delivered through electrodes placed on the wrist (USSEP) and on the ankle (LSSEP)
• For each of the tests the equipment will detect how long it takes for the impulse to travel from the place where you are being stimulated to the brain.  You will not feel the impulse go the whole way, only at the point of stimulation.
• Test takes about 45 minutes to one hour to complete

E.  How do I get my results?

Results from your test are generally completed within 24-48 hours.  The results will be communicated back to your physician that ordered the study.